Carton



14, 1967 M. 1. WILLIAMSON 3,35 7

' CARTON Filed Aug. 24, 1965 4 Sheets-Sheet l INVENTOR.

MARSHALL I. WILLIAMSON BY M 2/ZJW Hr: ATTORNEYS FlG.-l

1967 I I M WILLIAMSON 3,352,476

CARTON 4 Sheets-Sheet 5 Filed Aug. .24, 1965 FIG. 4

INVENTOR. MARSHALL I. WILLIAMSON BY M/ @722; 7

Hls ATTORNEYS Nov. 14, 1967' WILLIAMSON CARTON 4 Sheets-Sheet 4 Filed Aug. 24, 1965 INVENTOR. MARSHALL I. WILLIAMSON BY Ema; f

HI 5 ATTORNEYS United States Patent G 3,352,476 CARTON Marshall I. Williamson, New York, N.Y., assignor to Federal Paper Board Company, Inc., Bogota, N.J., a corporation of New York Filed Aug. 24, 1%5, Ser. No. 482,051 3 Claims. (Cl. 22939) ABSTRACT OF THE DI'StILOEURE A box or carton is constructed with closure flaps at its opposite ends which are so formed and interlocked with one another that tight joints are provided between the flaps which prevent the sifting of granular material and produce a non-sifting carton.

In cartons as formerly constructed the flaps projecting from the face and side panels were folded into overlapping relation to form the end closures, and these flaps extended the full carton thickness, so that the flaps overlapped one another from face to face as well as from side to side of the carton.

In order to save material, the so-called economy flaps were introduced, these consisting of narrow flaps extending from the side walls, and flaps on the front and back faces of the carton which overlapped merely enough to enable them to be glued together. Because of the tendency for such cartons to permit sifting of granular material, one of the flaps extending from the front or the back face of the carton was provided at its opposite ends with extensions which were folded against the sides of the carton and glued thereto to form ears.

The purpose of my present invention is to reduce still further the amount of material necessary to form the end flaps by providing flaps extending from the front and back carton faces which are so arranged that only certain portions of them will overlap one another in folded or closed position, but which will interlock with each other, and which when provided with the ears referred to, will produce a non-sifting carton.

In accordance with the invention, the flap projecting from one face wall of the carton is arranged with a wide mid-section which corresponds in width to the thicknes of the carton, and has wing sections on each side thereof which are considerably narrower. The flap projecting from the opposite face of the carton is just the reverse and is provided with wide wing sections at its opposite ends which correspond with the full width of the carton but this flap has a mid-section which is considerably nareach of the side walls of the carton, and each of these flaps has one sloping end or edge. On the flap which has the wide wing sections the ear members referred to are provided, and the edges of these slope at each end. When the carton is closed by means of the flaps described the wing sections are glued to the narrow end sections of the opposite flap and also to the narrow or conventional flaps, and the ear members are also glued to the outer side walls of the carton. The mid-section of the wide flap is glued to the outer surface of the mid-section of the opposite flap.

In closing the flaps the wide mid-section of one flap fits between the inner edges of the wide wing members on the opposite flap. That is to say, the end edges of the wide mid-section on one flap correspond closely to the distance between the inner edge of the wide wing members. The two flaps interlock with one another at these engaging points. Because of such interlocking, when the two flaps are folded to closed position, the squaring up of the end of the carton is brought about.

In order to take full advantage of the invention both ends of the carton will be constructed as described above. However, if desired, only the top of the carton may be constructed in accordance with the invention and the bottom of the 'carton may be sealed in any suit-able conventional manner. Inasmuch as the bottom end of a carton is ordinarily sealed upon a mandrel it is not difiicult to arrange and seal the flaps in such a way as to produce a tight, non-sifting closure, but in sealing the top end of a carton there is only the carton contents to resist the closing and sealing pressures so that with the usual or conventional arrangements of carton flaps, the tight sealing of the top end presents a problem.

The invention will be further understood from a consideration of the following explanation in connection with the accompanying drawings.

In these drawings:

FIG. 1 is a plan view showing the manner of simultaneously die cutting or stamping a plurality of blanks of one form from which the carton of the invention can be made;

FIG. 2 is a view similar to FIG. 1 showing a modified form of blank;

FIG. 3 is a perspective view of a carton made from the blank shown in FIG. 1 with the flaps at the top in extended position ready to be folded, and showing the bottom closed by the folding and gluing of its flaps;

FIG. 4 is a plan view of a carton having its top flaps extended to horizontal position and showing the inside of the bottom flaps in closed position;

FIG. 5 is a fragmentary plan view of the top of a carton after the flaps have been closed;

FIG. 6 is a photographic perspective view of the upper portion of a carton with the flaps closed;

FIG. 7 is a view similar to FIG. 4 showing a carton with the modified form of flaps;

FIG. 8 is a perspective view similar to FIG. 3 showing the modified form of carton;

FIG. 9 is a fragmentary view similar to FIG. 5 of the modified carton;

FIG. 10 is a perspective view similar to FIG. 6 of the modified carton; and

FIG. 11 is a fragmentary plan view similar to FIG. 5 showing a further modification.

The blank from which the preferred carton of the invention is made is shown in FIG. 1 in plan view. In fact three of these blanks are shown in end-to-end contiguous relation extending crosswise of a web 11 of paper board from which they are stamped by means of dies, or otherwise. The closure flaps at the opposite ends of the blanks are nested end to end with the closure flaps of adjacent blanks thus reducing wastage to a minimum. The blank which is indicated generally by reference numeral 12 comprises a back face panel 13, a front face panel 14 and side panels 15 and 16. The width of face panels 13 and 14 are the same and correspond to the width of the carton. Side panels 15 and 16 are also of equal width which corresponds to the thickness of the carton. Side panel 15 is joined to face panels 13 and 14 by fold or score lines 17 and 18, and side panel 16 is joined to panel 14 by a fold line 19. A glue lap 20 is joined by fold line 21 to the free side of rear panel 13.

Extending from each end of back face panel 13 there is a back closure flap having a wide mid-section 22 (FIGS. 1 and 4) whose width corresponds to the thickness of the carton, or the width of side panels 15 and 16. On each side of this mid-section are two narrow wing or flank sections 23 and 24. The width of the outer portions of these wing sections is only a fraction of the thickness of the carton.

Exetending from each end of front panel 14 there is a front closure flap having a narrow mid-section 25 and two wide wing sections 26 and 27. These wing sections have a maximum width which corresponds to the width of the side panels 15 and 16, or in other Words, to the thickness of the carton. The width of the mid-section 25, like the outer portions of wing sections 23 and 24, is only a fraction of the thickness of the carton.

In this form of blank the wide wing sections 26 and 27 of the front closure flap have inner edges which are convex as shown at 28 (FIGS. 3 and 4), and the outer edges of the narrow wing sections 23 and 24 of the rear closure flap have concave edges as shown at 29, and these edges have corresponding curvatures.

The back closure flap is joined to back panel 13 by a fold line 30 and the front closure flap is joined to panel 14 by fold line 31. Projecting from the side panels 15 and 16 there are narrow flaps 32 which are connected to these panels by fold line 31. Flaps 32 have sloping inner edges 33 which facilitate the folding of these flaps and also of the wide wing sections 26 and 27 of the front closure flap. Projecting laterally from these wind wing sections 26 and 27 there are ear members 34 and 35 which are sloped at both ends as is customary.

As shown and described full advantage of the invention is taken, and hence the closure flaps at the bottom of the blank are identical with the closure flaps at the top.

The length of mid-section 22 of the back closure flap, that is, the distance between the curved ends 36 and 37 at their bases closely corresponds to the distance between the edge portions 38 and 39 of wing members 26 and 27 of the front closure flap adjacent the edge of its midsection 25, or may be made somewhat greater than this distance, the object being to produce a jam fit or to crowd the edges or ends 36 and 37 against edge portions 38 and 39 when the two flaps are folded to horizontal or closed position as shown in FIGS. and 6.

In order to take full advantage of the invention, minute slits 40 and 41 are provided as a continuation of the edge portions 36 and 37 forming narrow lips 44 and 45 on wing portions 23 and 24. Also minute slits 42 and 43 (FIG. 4) are provided as extensions of edge portions 38 and 39 of wings 23 and 24, forming between them a long narrow lip 46. Short shoulders which are parallel with the fold line 39 are formed by the edges of lips 44 and 45. The opposite ends 36 and 37 of mid-section 22 are curved and become tangent to the convex edges 28 of the wing sections 26 and 27 when the two opposite closure flaps are folded to closed position (FIGS. 5 and 6).

In folding and setting up the blanks shown in FIG. 1 to form the carton of FIGS. 3-6, glue is applied to the glue lap 20 and also to the inside surfaces of mid-section 22 of the back closure flap and to the inside surfaces of wing portions 26 and 27 of the front closure flap and also to the inside surfaces of the ears 34 and 35. Such glue application can be made by conventionally automatic glue applicators modified to suit the particular purpose. The folding of the flaps and ears can also be done on conventionally automatic apparatus.

In setting up the carton, if desired, glue may be applied only to glue lap 20, followed by folding the front and back face panels 13 and 14 and side panels 15 and 16 about the respective fold lines 17, 18 and 19 bringing glue lap 20 near the free edge of side panel 16 Glue lap 20 is then brought into gluing engagement with the inte'rior surface of the margin of panel 16. This forms a semierected carton which may be collapsed by folding about the opposite fold lines 17 and 19, or 18 and 21 leaving the front and back closure flaps extending from and in the planes of the respective back and front face panels 13 and 14, and the narrow flaps 32, projecting from the respective side panels 15 and 16. The cartons may, if desired, be shipped to the consumer or user in such collapsed condition.

The bottom of the carton is closed before the top and by the same procedure which is about to be described. After filling the carton, the closure flaps at the top are folded to closed position in the following manner:

The back closure flap is folded toward the right in FIGS. 3 and 4 by pressure on its mid-section 22, and the front closure flap is simultaneously folded by pressure on its wing sections 26 and 27, the narrow flaps 32 on the side panels 15 and 16 are also being folded inwardly. During such folding the inner surfaces of the margins of wings 26 and 27 of the front closure flap adjacent the edge portions 38 and 39 press against the shoulders formed by the lip portions 44 and 45 on the back closure flap to assist in folding the wing sections 26 and 27. The curved ends 47 and 423 of mid-section 22 engage these edge portions 38 and 39 and a wedging action which takes place as the two closure flaps are swung to closed position as shown in FIGS. 5 and 6, which crowds the parts together and produces the jam fit previously referred to, and also causes the squaring up of the end of the carton.

As the folding operation is completed, the engagement of lips 44 and 45 beneath the marginal portions of wings 26 and 27 cause these lips to be tilted downwardly to a slight extent, about a line parallel with the fold line 30 and extending through the bottoms of cuts 40* and 41. Also the narrow elongated lip 46 extending along the edge of mid-section 25 of the front closure panel is similarly tilted or bent slightly in a downward or inward direction by its engagement with the inner surface of the base portion of mid-section 22 of the back closure panel.

As the two closure flaps reach their final position in contact with one another the slit 40 on the back closure flap interengages slit 42 in the front closure flap, and, similarly, slit 41 interengages slit 43. This produces a slitto-slit engagement and a sift-tight closure is formed at the intersecting points 47 and 48 of the two closure flaps where mid-section 22 of the back closure flap overlaps the midsection 25 of the front closure flap, and the Wing portions 26 and 27 of the front closure flap overlap the wing portions 23 and 24 of the back closure flap.

At the intersecting points 47 and 48 where the slit-toslit engagement takes place the surfaces of the respective flaps are displaced out of a common plane which causes a warping of the two closure flaps in the immediate vicinity of the intersecting points as may be seen in FIG. 6. The displacement occurs because the front portions of the upper surfaces of wing sections 26 and 27 are below the mid-section 22, the lower surface of which has contacted and is now glued to the upper surface of midsection 25. Such displacement is shown in FIG. 6 by the thickness of edge or end 37 of mid-section 22. Also, the rear portions of wing sections 26 and 27 are above the rear portions of wing sections 23 and 24, this being shown by the visible edges 28 of wing sections 26 and 27. This displacement and warping enhances the interengagements of the fibers at the slit-to-slit contact at points 47 and 48 and assists in producing tight joints.

In FIG. 4, the positions of the respective parts of the closure flaps at the bottom of the carton can be seen after the completion of the bottom folding operation. The narrow lips 44b and 45b overlie the surface of mid section 25b of the bottom front closure, flap. The elongated lip 46b of the bottom front closure flap overlies the marginal edge of the mid-section of the back bottom closure flap which in fact is invisible because concealed by mid-section 25b.

It will be understood that wing sections 26 and 27, on the completion of the closing operation, are glued in part to the outer surfaces of wing portions 23 and 24 of the back closure flap and in part to the upper surfaces of the narrow panels 32 which are connected to the respective side panels 15 and 16. As shown in FIG. 5, for example, the upper portion of narrow flap 32 above the dotted edge 29 of wing section 24 is in contact with the lower surface of wing section 27 and is glued thereto. Either simultaneously with or following the closing operation above described the two ears 34 and 35 are folded downwardly and glued to the opposite sides 15 and 16 of the carton, one of these ears 35 being shown in glued position in FIG. 6.

The positions of the glue areas above referred to and shown in FIGS. 3 and 4 are advantageous from a sealing or bonding pressure standpoint. The narrow mid-section 25 is swung downwardly by its two flanking wing sections 26 and 27. Because of the stiffness of the fold line 31, the parts resist folding, and because the mid-section 25 is narrow considerable upward thrust is produced which assists in the sealing or bonding operation with the glue on the inner surface of mid-section 22 of the back closure flap as it is pressed downwardly by the closing apparatus. Similarly the narrow widths of wing sections 23 and 24 of the back closure flap produce an upward thrust which facilitates their sealing by the downward pressure of wing sections 26 and 27 of the front closure flap. In this way good bonding is produced between all of the contacting surfaces.

In FIGS. 2 and 7-10 the modified carton blank and carton construction are the same as previously described except that the back and front closure flaps are of angular outline instead of rounded outline, and in addition, that the cuts 40, 41, 42 and 43 have been omitted and instead thereof two tiny radii or short curved sections are used at the intersecting points 47a and 48a (FIG. 10), which will be presently described. The various portions of the blank and of the carton shown in FIGURES 2 and 7-10 have been indicated by the same reference numerals as used in connection with FIGS. 1 and 2-6 but applying the sutfix small a to each numeral.

Referring now briefly in detail to the modified form of blank and carton, mid-section 22a of the back closure flap has angular sloping straight edges 36a and 37a which intersect shoulder portions 44a and 45a that are some what longer than the lip portions 44 and 45 (which also form shoulders). Shoulders 44a and 45a intersect the angular end portions 49 and 50 which replace the curved ends 29 of the form shown in the previous figures. The wing sections 23 and 24 of the back closure flap are the areas between fold line 30a and the edges 44a and 49 at the left end, and 45a and 50 at the right end.

The front closure flap has a mid-section 25a which is substantially the same as mid-section 25 previously described. The wing sections 26a and 27a however have straight edges 28a which are at an obtuse angle to the edge of mid-section 25a. Ears 34a and 35a project from the sides of these wing sections as before. Also narrow side flaps 32a project from the opposite sides a and 16a of the carton.

In this modified form of carton, the ends 36a and 37a of mid-section 22a intersect the shoulders 44a and 45a at the interengaging, interlocking or cross-over points 47a and 48a.

Also the sloping edges 28a of wing sections 26a and 27a intersect the edge of mid-section a at these same crossover points 47a and 48a. However, the distance between these cross-over points on the back closure flap closely corresponds to the distance between these points on the front closure fiap. The purpose is to cause the corners on the back closure flap at points 47a and 48a to crowd the corners on the front closure flap when these flaps are folded to closed position in order to produce a jam fit as in the case of the form of carton previously described.

Although the edges 36a, 37a and 28a of the two closure flaps may be straight up to the point of their intersections with edges 44a, 45a and the edge of mid-section 25a, this requires considerable precision in the stamping and folding of the blanks. Consequently, in order to take full advantage of the invention, tiny radii, forming minute curves,

are provided at the respective intersections of the shoulders 44a and 45a with the respective ends 36a and 37a of mid-section 22a. Also, similar minute curves are provided on the front closure flap at the intersection between sloping edges 28a and the edge of mid-section 25a. FIGS. 7-10 include these minute curved sections at the intersections mentioned.

The presence of these small curves at the interengaging points 47a and 480 not only enables the stamping and folding of the blanks with permissible tolerances, but produces the warping or puckering of the surfaces of the rear and front closure flaps previously mentioned, and indicated in FIGS. 9 and 10, and in addition a slight burring of the edges of the two flaps at the two interengaging points. This contributes to the production of tight joints between the two flaps. The overlying of wing portions 26a and 2711 on the outer surface of the wing portions to the left and right of mid-section 22a and the separation of the planes of these various parts is indicated in FIG. 10. Also there is shown in this figure, the overlying of mid-section 22a on the upper surface of mid-section 25a of the front closure flap.

The crowding and the jam fit wherein the parts referred to above, coming together with the presence of the tiny radii or minute curves at the interengaging points 47a and 48a between the two flaps causes a slight deflecting of the marginal edge of mid-section 25a between the two intersecting points, and also a slight deflecting of the marginal edges of the back closure flap outwardly from the two interengaging points. This is indicated where the edge portion 51 of mid-section 25c at the bottom of the carton may be seen and also the edges at 52 and 53 of the main body of the back closure flap.

It was mentioned above that the modified form of carton shown in FIGS. 2 and 7-10 may be constructed without the use of the tiny radii, or small curves at the Interlocking points 47a and 48a. The form of carton shown in FIGS. 1 and 3-6 may also be made without the presence of the minute slits 40, 41, 42 and 43. Such a carton is shown in FIG. 11 which corresponds with FIG. 5. The edge of mid-section 25d of the front closure flap is a continuous straight line to the interengaging point 48d. Shoulder 45d is in line with this edge to its intersection with the curved edge 29d of wing section 24 of the back closure flap. The intersection of the base of the end or edge 38d of mid-section 22d with the edge 28d of the front closure flap produces a burrin-g or puckering or warping of the surfaces of the two flaps at the interengagmg point 48d which is similar to that previously described in connection with the modified form of carton shown in FIGS. 2 and 7-10.

As may be seen in FIGS. 5, 6 and 9, 10 the formation of the carton end closures in accordance with the present invention imparts attractiveness to the carton because the carton presents the appearance of an overwrapped package. Another advantage is the fact that the wide central portion of the back closure flap in either form of the invention and including the mid-section 22 and 22a provides suflic ent space for uninterrupted illustration or display printing.

From the point of view of the saving in manufacturing cost, when made as shown and described, the present carton has the advantage that the closure flaps, front and rear, of either the form shown in FIG. 1 or that shown in FIG. 2 nest with one another across the width of the paper board web 11, so that there is substantially no waste except for very narrow strips along each side of the web, and at the opposite ends of the web. Since several hundred blanks may be made from a single web, i.e., a single roll, the waste at the ends is insignificant. Should it be desired to use some conventional form of closing flaps at the bottom of the carton there will still be a considerable saving in the amount of waste but the saving will not be as large as when both ends of the carton are closed in accordance with the invention.

It will be understood that with either form of the carton flaps as shown in FIG. 1 or FIG. 2 the bringing together of the front and back closure flaps squares up the end of the carton with a considerable degree of precision.

I claim:

1. A carton blank having front and back face panels connected by fold lines with an intermediate side panel, one of the face panels having a second side panel c nnected thereto by a fold line and the second face panel supporting a glue lap, and foldable end flaps connected by score lines with the opposite ends of the respective face panels, the flaps on the opposite ends of the second face panel having each a wide mid-section whose width corresponds with that of the side panels and also having wing sections which are narrower, and the flaps connected to the opposite ends of the first face panel having wide wing sections whose width corresponds to the side panels and also having each a mid-section which is narrower, a narrow flap connected by a fold line with each end of each side panel, said narrow flaps each having one sloping end, and an ear member having sloping ends connected to each of the wide Wing sections, with one sloping end of said ear adjacent the sloping end of the narrow flap.

2. A carton having parallel front and back face panels, parallel side panels at right angles to the face panels, and at least one end closed by means of folded flaps connected by score lines with said respective panels, characterised in that the flap connected to one face panel has a wide mid-section whose width corresponds to the carton thickness and Wing sections which are narrower, and the flap connected to the opposite face panel has wide wing sections whose width corresponds to the carton thickness and a mid-section Which is narrower, when the fiaps are folded to closed position said Wide mid-section overlapping said narrower mid-section, and said wide wing sections overlapping said narrower Wing sections, the ends of the wide mid-section of one closure flap being interlocked with the edges of the wide wing sections of the op posite closure flap, the edges of the wide mid-section of one closure flap being wedge shaped and having minute slits in the wing portions thereof in line with such edges, and the edges of the Wide wing sections of the opposite closure flap being curved outwardly from the edge, of the mid-section of such flap, minute slits being cut in said mid-section in line with said curved edges, when said flaps are in closed position said wing slits and mid-section slits being in engagement with one another so as to form a sift proof closure between the mid-section of one flap and the wing sections of the opposite flap.

3. A carton as set forth in claim 2 wherein the opposite flaps engage one another with a jam fit which produces a warping of the surfaces of the flaps at the points of slitto-slit engagement thereof.

References Cited UNITED STATES PATENTS JOSEPH R. LECLAIR, Primary Examiner.

R. PESHOCK, Assistant Examiner. 

1. A CARTON BLANK HAVING FRONT AND BACK FACE PANELS CONNECTED BY FOLD LINES WITH AN INTERMEDIATE SIDE PANEL, ONE OF THE FACE PANELS HAVING A SECOND SIDE PANEL CONNECTED THERETO BY A FOLD LINE AND THE SECOND FACE PANEL SUPPORTING A GLUE LAP, AND FOLDABLE END FLAPS CONNECTED BY SCORE LINES WITH THE OPPOSITE ENDS OF THE RESPECTIVE FACE PANELS, THE FLAPS ON THE OPPOSITE ENDS OF THE SECOND FACE PANEL HAVING EACH A WIDE-SECTION WHOSE WIDTH CORRESPONDS WITH THAT OF THE SIDE PANELS AND ALSO HAVING WING SECTIONS WHICH ARE NARROWER, AND FLAPS CONNECTED TO THE OPPOSITE ENDS OF THE FIRST FACE PANEL HAVING WIDE WING SECTION WHOSE WIDTH CORRESPONDS TO THE SIDE PANELS AND 